[Bf-blender-cvs] [f4982b555c3] master: Fix undo misdetecting identical future chunk in some cases

[Brecht Van Lommel]

Commit: f4982b555c340348a50ee80df0a4bf11074d3b1d
Author: Brecht Van Lommel
Date:   Sat Mar 28 21:48:07 2020 +0100
Branches: master
https://developer.blender.org/rBf4982b555c340348a50ee80df0a4bf11074d3b1d

Fix undo misdetecting identical future chunk in some cases

Clear is_identical_future before adding a next undo step, to avoid wrong
values for cases where we undo and then add a step with different changes
than what was previously the next step.

Ref D7274

===================================================================

M	source/blender/blenkernel/intern/blender_undo.c
M	source/blender/blenloader/BLO_undofile.h
M	source/blender/blenloader/intern/undofile.c

===================================================================

diff --git a/source/blender/blenkernel/intern/blender_undo.c b/source/blender/blenkernel/intern/blender_undo.c
index 99eb4dc9122..ab382d0e8ff 100644
--- a/source/blender/blenkernel/intern/blender_undo.c
+++ b/source/blender/blenkernel/intern/blender_undo.c
@@ -124,6 +124,9 @@ MemFileUndoData *BKE_memfile_undo_encode(Main *bmain, MemFileUndoData *mfu_prev)
   }
   else {
     MemFile *prevfile = (mfu_prev) ? &(mfu_prev->memfile) : NULL;
+    if (prevfile) {
+      BLO_memfile_clear_future(prevfile);
+    }
     /* success = */ /* UNUSED */ BLO_write_file_mem(bmain, prevfile, &mfu->memfile, G.fileflags);
     mfu->undo_size = mfu->memfile.size;
   }
diff --git a/source/blender/blenloader/BLO_undofile.h b/source/blender/blenloader/BLO_undofile.h
index 5f1142cc20e..f280b8f3b9c 100644
--- a/source/blender/blenloader/BLO_undofile.h
+++ b/source/blender/blenloader/BLO_undofile.h
@@ -60,6 +60,7 @@ extern void memfile_chunk_add(MemFile *memfile,
 /* exports */
 extern void BLO_memfile_free(MemFile *memfile);
 extern void BLO_memfile_merge(MemFile *first, MemFile *second);
+extern void BLO_memfile_clear_future(MemFile *memfile);
 
 /* utilities */
 extern struct Main *BLO_memfile_main_get(struct MemFile *memfile,
diff --git a/source/blender/blenloader/intern/undofile.c b/source/blender/blenloader/intern/undofile.c
index 06469a0c087..69c4ba2b1f2 100644
--- a/source/blender/blenloader/intern/undofile.c
+++ b/source/blender/blenloader/intern/undofile.c
@@ -92,6 +92,14 @@ void BLO_memfile_merge(MemFile *first, MemFile *second)
   BLO_memfile_free(first);
 }
 
+/* Clear is_identical_future before adding next memfile. */
+void BLO_memfile_clear_future(MemFile *memfile)
+{
+  for (MemFileChunk *chunk = memfile->chunks.first; chunk; chunk = chunk->next) {
+    chunk->is_identical_future = false;
+  }
+}
+
 void memfile_chunk_add(MemFile *memfile, const char *buf, uint size, MemFileChunk **compchunk_step)
 {
   MemFileChunk *curchunk = MEM_mallocN(sizeof(MemFileChunk), "MemFileChunk");